(1) Field of the Invention
This invention relates to a laminated film of an olefin polymer. More particularly, this invention relates to a laminated film of which at least one side is mat finish, having excellent delustering quality, excellent adhesion of the delustered surface whose delustering quality is not lost during a processing at elevated temperature and pressure, etc., and more particularly, relates to a laminated film having a delustered surface on one side and a smooth surface on the other side, wherein the both sides have high adhesion to a metallized layer or paper.
(2) Description of the Prior Art
Conventional laminated films include a film prepared by lamination of ethylene/propylene block copolymer films (see, for example, Japanese Patent Publication No. 32954/1982) and a film prepared by lamination of films of a blend prepared from polypropylene and high-density or low-density polyethylene.
These conventional laminated films, however, can not show sufficient delustering property or require a mat layer which is thick enough to obtain the desired delustering quality, so that they have suffered a drawback that the total light transmittance is lowered. Further, because the peaks of their melting curves lie at a temperature below 120.degree. C., they have another drawback that the dullness is lost when elevated pressure and heat are applied in laminating with paper, for example, in print laminating.
On the other hand, studies have been made on the application of laminated paper prepared by laminating a metallized film with paper, instead of conventional aluminum foil. Such a laminate is used inside wrapping paper of cigarettes which requires a gas barrier property, or as paper for use in making fancy boxes for European wine or strong drink etc., which must be matted to give an appearance of quality products. This use is because of an abrupt rise of the price of the aluminum foil and the drawback of its liability to wrinkle during handling.
These laminated papers, however, are not satisfactory in adhesive strength between the film and the metallized layer or a print layer, so that they are easily damaged and peeled by friction.